Conveyer traction block



A g- 19, 1952 P. A. SOLEM CONVEYER TRACTION BLOCK Filed Jan. 15, 1949Peter Salem Patented Aug. 19, 1952 CONVEYER TRACTION BLOCIK v I PeterS'olem, Rockford, Ill. Q .2, 1

Application January 15, 1949, Serial No. 71,113

This invention relates to a new and improved traction block forfurnishing a cushion traction surface on the traveling work-feeding bedor carrier of a sanding machine, or the. like, and is more particularlyconcerned with improvements stamped sheet metal insert to enable themore secure fastening of the block to the bed, and

having in the work-engaging top face depressions long enough and wideenough to give a suction cup effect for increased traction and at thesame time decrease the'transverse wall thicknesses at all points aroundthese depressions so that a higher degree of cushioning effect isobtained, without, on the other hand, weakening the block to an extentwhere the rubber is apt to tear or wear away too soon at any point, theaim being to obtain substantially uniform wear throughout the area ofthe working face of the block.

The invention is illustrated in the accompanying drawing, in which- Fig.1 is a plan view of a traction block made in accordance with myinvention, showing the elongated depressions in the working face, whichare placed in communication with one another by the central counterboreprovided in the block in concentric relation to the center hole in themetallic anchoring insert;

Fig. 2 is a. horizontal section through the block, taken on the line 2-2of Fig. 3, showing the insert in elevation;

Fig. 3 is a cross-section on the line 33 of Fig. 1, and

Fig. 4 is a perspective view of a portion of an endless bed sandershowing the feed bed thereof equipped with my improved traction blocks.

The same reference numerals are applied to corresponding parts in thethree views.

Sanding machines generally include an endless work-feeding bed orcarrier, as illustrated at A in Fig. 4, on which rows of traction blocksB are mounted to provide a good friction hold on the work being fedtoward and beneath the sanding drum, or drums, operating above the bed.The bed is usually built up of cross-bars or slats linked together, eachhaving a row of traction blocks fastened thereon, whereby to enablereplacement of individual blocks whenever some become worn or may happento be damaged. The blocks are mounted in spaced relation, with theblocks of one row usually placed in staggered relation with the blocksof the next row, and

. 'Z 'CIaims. (c1. 19s 197) so on. The blocks B are made ofresilientmaterial, such as vulcanized rubber, and each is fastened to the bed bya flat headed 'screw,-the head ofwhich is'disposed well below the top ofthe block, so that there is no danger of its cominginto contact'with thework. r

I'n'my earlier patent I disclose a traction'block of the kind justdescribed made of vulcanized rubber and having a metallic coreplate-embedded therein through which the fastening screw, justmentioned, extends for fastening the block to the bed, the metallicinsert also serving to reinforce the block against excessive flexurewithout, on the other hand, reducing its cushioning action too much. Theimprovements of the present invention are designed to increase thetraction and at the same time increase the cushioning action without, onthe other hand, weakening the blocks structural strength or giving riseto its wearing unevenly or tearing.

Referring to the drawing, the reference numeral 4 designates the bodyportion of the traction block B, molded of a rubber stock to thegenerally rectangular or square form shown, with rounded corners 5. B isthe stamped sheet metal insert or core plate, the central portion 1 ofwhich is depressed and of generally conical form with a key notch 8extending radially from the center hole 9. The notch 8 receives alocating projection on the bed, to keep the block from turning when itis secured in the usual way, as by means of a screw I0, indicated indotted lines in Fig. 3. Large apertures II in the four corners of thegenerally rectangular plate 6, and four other smaller apertures I2therebetween, all serve to insure a good bond between the molded rubberbody 4 of the block and the plate 6.

Referring to Figs. 1 and 3, it will be seen that, in addition to thecounterbore I3 provided in the center of the block, opening from theflat top or work-engaging face I4, in register with the depressedcentral portion I of the insert 6, the block has two parallel grooves ordepressions I5 in the top face, which are closed at both ends, as at IE,but are preferably in intersecting relation to and, hence, opencommunication with the diametrically opposite sides of the counterbore[3, as indicated at IT. Thus, when the workdegree, as when a suction cupis compressed for application to a surface to be gripped, so that farbetter traction is obtained and the likelihood of slippage of the workis reduced to a minimum. The grooves I5 are of appreciable depth inrelation to the thickness of the block, as appears in Fig. 3; and alsoof appreciable length and width in relation to the length and width ofthe block, as appears in Fig. 1, so as to make for easier give andaccordingly increase the cushioning action of theblock and, likewise,its suction cup effect, without, however, weakening the block to thepoint where there is any danger of the rubber tearing or wearing awaytoo rapidly or unevenly.

It is believed the foregoing description conveys a good understanding ofthe objects and advantages of my invention. The appended claims havebeen drawn to cover all legitimate modifica tions and adaptations. a

I claim:

1. A traction block adapted for use on a travel,- v

ing' work-feeding bed in an endless bed sander and the like comprising acentrally apertured, substantially rectangular 'body of resilientcompressible material, said body being of appreciable thickness which issmall in relation to its other dimensions and havinga substantiallyflat-work- ,engaging face, said body having a counterbore providedtherein extending from the working face part way throughthe thickness ofthe body in register-with the central aperture adapted-to eluding ametallic core plate embedded within said body which is centrallycountersunk and apertured, the countersunk portion registering with thecounterbore and aperture in said-body, but saidplate otherwise lying ina median plane in said body, the grooves in the body beingshallow'enough to leave an appreciable thickness of rubber above theplane of the plate between the plate and the bottoms fof the grooves.

' i g, PEIER A. 'SOLEM.

7 aEFERsNcEs erran V M The following references are of record in thefile of this patent: i

UNITED STATES PATENTS

